Combinations of HMG CoA reductase inhibitors, the so-called "statins," and other types of lipid regulating agents are known in the art in the treatment of Low Density Lipoprotein (LDL) Cholesterol. Unfortunately, one or more of these agents suffer from various drawbacks. At least some members of the reductase inhibitor family, in particular lovastatin, are very poorly soluble in water. This results in low bioavailability to the patient. Other agents, such as niacin (nicotinic acid), have much higher solubilities, but can be toxic to the patient or produce discomforting symptoms. Liver damage is thus a concern when treating for hyperlipidemia with niacin. In addition, niacin can produce gastrointestinal problems when taken in an immediate release composition administered several times daily. "Flushing" is another common occurrence in which painful swelling in the joints and elsewhere occurs for some minutes after ingestion.
U.S. Statutory Invention registration H1286, published Feb. 1, 1994, discusses various combinations of HMG CoA reductase inhibitors with agents which lower lipids via other mechanisms. Niacin, or nicotinic acid, is among the agents discussed.
U.S. Pat. No. 5,260,305 shows combinations of pravastatin and nicotinic acid and methods for lowering serum cholesterol levels with such combinations. The use of between 75 and 2,000 mg of nicotinic acid is disclosed.
U.S. Pat. No. 5,157,025 relates to methods for lowering serum cholesterol which employ phosphorous-containing ACE inhibitors in combination with other cholesterol lowering agents. Nicotinic acid is recited at column 20, line 61.
While combinations of lipid lowering agents are known, there is still a need for combinations in which each of the types of active components therein have been specifically formulated in order to optimize their release properties and, thereby, significantly minimize the likelihood that they will produce unwanted side effects when consumed. At the same time, there is a need for a dosage regimen which is more convenient to the patient than those currently available in the art. This invention addresses that need.